Ecosystem Function

Question 1

What is ecosystem function?

Answer 1

What a species does in an ecosystem

Question 2

When do you get more species in relation to niche use?

Answer 2

Range of resources is greater

Resource axis is fully exploited - community is fully saturated

Specialisation of species

Each species overlaps more with neighbour

Question 3

Give the different relationships between community function and species richness

Answer 3

Two main hypothesis:

Complementary = 1:1 ratio

Redundancy = >1:1 ratio

Complementary and keystone = each species adds function but one species has disproportionate impact

Redundancy and keystone = overlap between most species but one species has disproportionate impact

Question 4

What is the relationship between biodiversity and function

Answer 4

Originally denoted as hump-back curve

Used more data sets and found no relationship and hump-back curve not applicable to most ecosystems AKA productivity is a poor predictor of plant species richness

Analysis of all sites finds humpback again so may apply across ecosystem relationships BUT it is reliant on anthropogenic sites as natural sites of a linear line

Question 5

What is multifunctionality?

Answer 5

More than one species had a beneficial effect on each function - species overlap

The more functions you consider, the more species have a positive effect

Different processes are not affected by the same species so maintaining functions requires greater biodiversity